Numerous rotary vane pumps have been devised for pumping fluid. However, most of the known rotary vane pumps have been found to be relatively inefficient in operation and complex in structure. Known rotary vane pumps also are subject to excessive wear of the moving parts. Known rotary vane pumps do not have good seal characteristics between moving parts.
It is therefore an object of this invention to provide a rotary vane pump which is efficient in operation, and which does not have parts which wear excessively.
It is another object of this invention to provide such a rotary vane pump in which "back-flow" does not occur.
Another object of this invention is to provide such a rotary vane pump in which the bearings are readily accessible for inspection.
It is another object of this invention to provide such a rotary vane pump which can be produced and operated at relatively low costs.
It is another object of this invention to provide a rotary vane pump which is capable of pumping a gaseous material and which also includes means for introduction of a lubricant into the pump for lubrication, for sealing and for cooling the pump.
It is another object of this invention to provide such a rotary vane pump which includes means for controlling circulation of the lubricant through the pump.
Other objects and advantages of this invention reside in the construction of parts, the combination thereof, tee method of production and the mode of operation, as will become more apparent from the following description.